When Gollum led Frodo and Sam into Shelob's Lair, Frodo exclaims in Quenya, "Aiya Eärendil Elenion Ancalima!"; this translates as "Hail Eärendil, brightest of stars!". This is in reference to the light of the star of Eärendil, the Silmaril he wore upon his brow, the brightest star in the sky. It was the light of this star which is trapped within the Star-glass.

Upon Frodos departure from Middle-earth, the light from the phial faded as it reached the shores of Eldamar.